Channel Access Procedures for User Equipment

The present disclosure generally relates to wireless communication, and in particular, to channel access procedures for user equipment.

Harmonious management of legacy user equipment (UEs) and new UEs is a complex and evolving field. As cellular standards evolve, it is critical that new features of the cellular protocol do not negatively impact legacy UEs. Recent evolution of the 5G New Radio (NR) standards involve the implementation of 3 MHz channels, as well as 5 MHz channels with new Physical Broadcast Channel (PBCH) designs. Legacy UEs are not equipped to camp on cells serving less than 5 MHz channels. A manner of preventing legacy UEs from camping on such cells is needed.

Some exemplary embodiments are related to a method performed by a user equipment (UE). The method includes receiving, from a target cell, a cell identification (ID) number and determining the cell ID number is in one of a first range of values or a second range of values, wherein the first range of values indicates a channel being served by the target cell is a first type of channel and the second range of values indicates the channel being served by the target cell is a second type of channel.

Other exemplary embodiments are related to a method performed by a base station. The method includes broadcasting a cell identification (ID) number, wherein the cell ID number is in one of a first range of values or a second range of values, wherein the first range of values indicates a channel being served by the base station is a first type of channel and the second range of values indicates the channel being served by the base station is a second type of channel and when a user equipment (UE) supports the first type and the second type of channel, permitting an access attempt by the UE.

Still further exemplary embodiments are related to a method performed by a user equipment (UE). The method includes receiving a master information block (MIB) from a target cell, decoding the MIB, determining, based on information in the MIB, a channel served by the target cell is barred and determining, based on further information in the MIB, that the UE is not barred from using the channel.

Other exemplary embodiments are related to a method performed by a base station. The method includes encoding a master information block (MIB) for a channel served by the base station, the MIB comprising a value of a first information element (IE) indicating a first type of user equipment (UE) is barred from accessing the channel, the MIB further comprising a value of a second IE indicating a second type of UE can access the channel and broadcasting the MIB.

The exemplary embodiments may be further understood with reference to the following description and the related appended drawings, wherein like elements are provided with the same reference numerals. The exemplary embodiments relate to enhanced cell search differentiation procedures for legacy and new UEs.

The exemplary embodiments are described with regard to a UE. However, reference to a UE is merely provided for illustrative purposes. The exemplary embodiments may be utilized with any electronic component that may establish a connection to an accessory device and is configured with the hardware, software, and/or firmware to exchange information and data with accessory devices. Therefore, the UE as described herein is used to represent any electronic component.

The exemplary embodiments are also described with reference to a 5G New Radio (NR) network. However, it should be understood that the exemplary embodiments may also be implemented in other types of networks, including but not limited to LTE networks, future evolutions of the cellular protocol (e.g., 6G), or any other type of network.

Sub-5 MHz channels introduced in recent evolutions of the cellular protocols may be applicable to legacy bands, in which legacy UEs operate. Numerous issues are presented by such a scenario. Legacy UEs may attempt to decode synchronization signal blocks (SSBs) to receive a Master Information Block (MIB) relevant to the determination of whether a legacy UE may camp on a particular cell. Preventing such behavior is desirable to prevent wasted legacy UE signaling and power use in fruitless attempts to use sub-5 MHz channels.

While modification of the synchronization raster for new channel designs (and new UEs that support new channel designs) is possible, there are several issues with such an approach. The first is that the total number of raster points increases for future UEs that support such an implementation (as well as legacy implementations). Another issue is that due to narrow frequency separation between any two adjacent raster points, a UE may not be able to accurately differentiate which raster point it is decoding a Physical Broadcast Channel (PBCH) due to initial local oscillator frequency inaccuracy.

1 Proposed punctured PBCH designs may cause undesirable behavior with legacy UEs attempting to access cells utilizing new channel designs. Specifically, a legacy UE may still be capable of decoding a new-design PBCH and continue to receive a system information block (SIB)to obtain the information element (IE) carrierBandwidth. The legacy UE will then determine that it cannot access the channel, wasting both time and energy. It is desirable to stop the cell selection attempt of a legacy UE as soon as possible to reduce legacy UE power and signaling.

One of skill in the art will recognize that the existing physical cell ID (PCI) range is [0-1007], allowing for 1008 possible PCIs. According to some exemplary embodiments, extending the PCI range (e.g., [1008-2015]) will allow legacy UEs to determine that Primary Synchronization Signal (PSS) and Secondary Synchronization Signal (SSS) detection operations are unsuccessful. A legacy UE would be aware that any PCI beyond 1007 is not a cell that the legacy UE can access. Such a determination would cause a legacy UE to move on to a next raster point (e.g., the legacy UE will not access the new channel).

1 FIG. 100 100 110 110 110 shows an exemplary network arrangementaccording to various exemplary embodiments. The exemplary network arrangementincludes a UE. Those skilled in the art will understand that the UEmay be any type of electronic component that is configured to communicate via a network, e.g., mobile phones, tablet computers, desktop computers, smartphones, phablets, embedded devices, wearables, Internet of Things (IoT) devices, etc. It should also be understood that an actual network arrangement may include any number of UEs being used by any number of users. Thus, the example of one UEis merely provided for illustrative purposes.

110 100 110 120 110 110 110 120 110 120 The UEmay be configured to communicate with one or more networks. In the example of the network arrangement, the network with which the UEmay wirelessly communicate is a 5G NR radio access network (RAN). However, it should be understood that the UEmay also communicate with other types of networks (e.g., 5G cloud RAN, a next generation PAN (NG-RAN), a legacy cellular network, etc.) and the UEmay also communicate with networks over a wired connection. With regard to the exemplary embodiments, the UEmay establish a connection with the 5G NR PAN. Therefore, the UEmay have a 5G NR chipset to communicate with the NR PAN.

120 120 120 120 The 5G NR PANmay be portions of a cellular network that may be deployed by a network carrier (e.g., Verizon, AT&T, T-Mobile, etc.). The PANmay include cells or base stations that are configured to send and receive traffic from UEs that are equipped with the appropriate cellular chip set. In this example, the 5G NR PANincludes the gNBA. However, reference to a gNB is merely provided for illustrative purposes, any appropriate base station or cell may be deployed (e.g., Node Bs, eNodeBs, HeNBs, eNBs, gNBs, gNodeBs, macrocells, microcells, small cells, femtocells, etc.).

110 120 120 110 120 110 120 110 120 120 120 120 1 FIG. Those skilled in the art will understand that any association procedure may be performed for the UEto connect to the 5G NR PAN. For example, as discussed above, the 5G NR PANmay be associated with a particular network carrier where the UEand/or the user thereof has a contract and credential information (e.g., stored on a SIM card). Upon detecting the presence of the 5G NR PAN, the UEmay transmit the corresponding credential information to associate with the 5G NR PAN. More specifically, the UEmay associate with a specific cell (e.g., gNBA). There may also be one or more neighboring cells with which the UE may communicate with prior to a handover operation. One additional neighbor cell is shown inwith gNBB, but one of skill in the art will recognize that a UE may have more than one neighbor cell available for handover. The gNBB may have differing channel designs than the gNBA.

100 130 140 150 160 130 140 150 110 150 130 140 110 160 140 130 160 110 The network arrangementalso includes a cellular core network, the Internet, an IP Multimedia Subsystem (IMS), and a network services backbone. The cellular core networkmanages the traffic that flows between the cellular network and the Internet. The IMSmay be generally described as an architecture for delivering multimedia services to the UEusing the IP protocol. The IMSmay communicate with the cellular core networkand the Internetto provide the multimedia services to the UE. The network services backboneis in communication either directly or indirectly with the Internetand the cellular core network. The network services backbonemay be generally described as a set of components (e.g., servers, network storage arrangements, etc.) that implement a suite of services that may be used to extend the functionalities of the UEin communication with the various networks.

2 FIG. 1 FIG. 110 110 100 110 205 210 215 220 225 230 230 110 110 shows an exemplary UEaccording to various exemplary embodiments. The UEwill be described with regard to the network arrangementof. The UEmay represent any electronic device and may include a processor, a memory arrangement, a display device, an input/output (I/O) device, a transceiver, and other components. The other componentsmay include, for example, an audio input device, an audio output device, a battery that provides a limited power supply, a data acquisition device, ports to electrically connect the UEto other electronic devices, sensors to detect conditions of the UE, etc.

205 110 235 110 The processormay be configured to execute a plurality of engines for the UE. For example, the engines may include a cell selection enginefor performing operations related to determining whether the UEwill continue a cell selection procedure with a target cell utilizing a new channel design.

205 110 110 205 The above referenced engine being an application (e.g., a program) executed by the processoris only exemplary. The functionality associated with the engines may also be represented as a separate incorporated component of the UEor may be a modular component coupled to the UE, e.g., an integrated circuit with or without firmware. For example, the integrated circuit may include input circuitry to receive signals and processing circuitry to process the signals and other information. The engines may also be embodied as one application or separate applications. In addition, in some UEs, the functionality described for the processoris split among two or more processors such as a baseband processor and an applications processor. The exemplary embodiments may be implemented in any of these or other configurations of a UE.

210 110 215 220 215 220 225 120 225 The memory arrangementmay be a hardware component configured to store data related to operations performed by the UE. The display devicemay be a hardware component configured to show data to a user while the I/O devicemay be a hardware component that enables the user to enter inputs. The display deviceand the I/O devicemay be separate components or integrated together such as a touchscreen. The transceivermay be a hardware component configured to establish a connection with the 5G-NR PAN. Accordingly, the transceivermay operate on a variety of different frequencies or channels (e.g., set of consecutive frequencies).

3 FIG. 300 300 120 120 110 shows an exemplary base stationaccording to various exemplary embodiments. The base stationmay represent the gNBA (or the gNBB) or any other access node through which the UEmay establish a connection and manage network operations.

300 305 310 315 320 325 325 300 The base stationmay include a processor, a memory arrangement, an input/output (I/O) device, a transceiver, and other components. The other componentsmay include, for example, an audio input device, an audio output device, a battery, a data acquisition device, ports to electrically connect the base stationto other electronic devices and/or power sources, etc.

305 110 330 110 The processormay be configured to execute a plurality of engines for the UE. For example, the engines may include a cell selection enginefor performing operations related to transmission of information that the UEwill use to determine whether to continue a cell selection procedure with a target cell utilizing a new channel design.

310 300 315 300 320 110 100 320 320 The memory arrangementmay be a hardware component configured to store data related to operations performed by the base station. The I/O devicemay be a hardware component or ports that enable a user to interact with the base station. The transceivermay be a hardware component configured to exchange data with the UEand any other UE in the network arrangement. The transceivermay operate on a variety of different frequencies or channels (e.g., set of consecutive frequencies). Therefore, the transceivermay include one or more components (e.g., radios) to enable the data exchange with the various networks and UEs.

In a first aspect of the exemplary embodiments, an enhanced PCI range for new channel designs is disclosed. In the first aspect, the PCI range is extended from [0-1007] to include [1008-2015]. Shown below is Equation 1, which may be utilized to generate an extended PCI space beyond existing implementations.

One of skill in the art will recognize that

is used for PSS sequence generation and both

are used in SSS generation.

Expansion of the PCI space may also be enhanced by way of three alternatives. In a first alternative,

may become a value from [336-671] during SSS generation. In a second alternative, both

may be modified to give a PCI range of [1008-2015]. In a third alternative, the range of a PCI may differ from [1008-2015] or may not provide the same number of unique cell IDs of 1008.

In a second aspect of the exemplary embodiments, six possible sequences of length-127 may be used for PSS generation in equation 2, disclosed below:

In a third aspect of the exemplary embodiments, an enhanced SSS sequence generation is disclosed. In the third aspect,

may range from {0, 1, 2, 3, 4, 5}. Equation 3 shows an enhanced means of SSS generation for cell search differentiation between legacy and new UEs in sub-5 MHz channels.

It should be understood that the above values for the first through the third aspects are only exemplary. One of skill in the art will understand that if the PCI is expanded in a different manner, e.g., not [1008-2015], the values described for the second and third aspects may also be different. However, since the manner of deriving these values have been described herein, e.g., equations 1-3, one skilled in the art will understand how to modify the parameters and/or parameter values of equations to obtain different values.

4 FIG. 400 400 400 In a fourth aspect of the exemplary embodiments, enhanced MIB operations for legacy UEs are disclosed herein.shows an enhanced Master Information Block (MIB), according to various exemplary embodiments. The MIBmay be applicable to scenarios in which a legacy UE is attempting to access a cell utilizing new channel sizes (e.g., sub-5 MHz). The MIBmay also be applicable to scenarios in which a new UE is attempting to access a cell utilizing a new channel design.

110 110 110 400 400 405 405 410 Following initial synchronization procedures of a UE (e.g., the UE) with a network, the UEwill begin to receive information blocks from the network. One information block that the UEwill receive from the network is the MIB. The MIBmay contain Information Elements (IEs)related to cell selection (e.g., system frame number, subcarrier spacing, subcarrier offset, etc.) Each information element of IEsmay have a corresponding field. For example, systemFrameNumber corresponds with “Bit String (Size (6))”.

405 410 400 400 One of skill in the art will recognize that each IEand its corresponding fieldhave a defined bit sequence size. The MIBhas 24 bits available, of which 23 bits are used. This leaves an additional bit for an IE, which is labeled in the MIBas “spare” and will be discussed below.

The “barred” value may be indicated for the cellBarred IE. In the scenario that a legacy UE successfully decodes PBCH MIB information, the legacy UE will know that the cell is barred from access. In a similar manner, “notbarred” may be used to indicate to both new UEs and legacy UEs that the cell is accessible (along with corresponding new channels).

400 Consequently, the new channel is accessible only to new UEs, and not legacy UEs. When a new UE decodes “barred”, however, the new UE may actually support the channel of the target cell. In such a case, a new UE may continue after decoding “barred” and decode the “spare” IE of the MIB. The “spare” IE has a single bit value that may be used to indicate to new UEs that they may continue their cell selection procedure.

It should be understood that the term “spare” for the IE containing the “extra” bit is only exemplary and may change with future evolutions of cellular standards. It should also be understood that there is no particular value that the “spare” IE needs to take for a UE capable of accessing a new channel design of a target to continue the cell selection procedure. In other words, operator implementation can dictate whether 1 or 0 in the “spare” IE field causes new UEs to continue the cell selection procedure.

5 FIG. 4 FIG. 500 500 400 500 110 120 110 120 120 shows a first method diagramaccording to various exemplary embodiments. The method diagrammay be understood to incorporate the MIBshown in. The method diagrammay be understood to be applicable to scenarios wherein a UE (e.g., the UE) is attempting to access a target cell (e.g., the gNBB) utilizing a new channel design (e.g., sub-5 MHz). It should be understood that the UEmay be camped on a first cell (e.g., the gNBA) and is considering whether to switch to a new target cell (e.g., the gNBB).

502 110 400 120 504 110 506 110 400 110 508 508 110 120 In, the UEreceives a Master Information Block (e.g., the MIB) from the gNBB (the target cell). In, the UEdecodes the MIB. In, the UEdetermines the presence of “barred” in the cellBarred IE contained in the MIB. If “barred” is not present, the UEcontinues to. In, the UEcontinues the cell access procedure with the gNBB.

110 400 110 510 110 110 506 512 120 120 110 110 120 If the UEdetermines that “barred” is present in the cellBarred IE contained in the MIB, the UEcontinues to. It should be noted that if UEis a legacy UE, the UEwould cease the selection procedure if the answer tois yes and would proceed toand omit an attempt to access the gNBB. Omitting the attempt to access the gNBB after determining the cell is barred saves energy and time at the legacy UE, because the legacy UEwill not continue along an ultimately fruitless cell selection attempt of the gNBB utilizing a new channel design.

510 110 120 110 400 110 508 120 120 In, if the UEis a new UE capable of accessing the new channel design offered by the gNBB, the UEdetermines the presence of an additional value in the “spare” bit of the MIB. Again, it should be understood that the particular value of the spare bit may be left to operator implementation or may be defined by standard (e.g., 3GPP standards). If the further value for the “spare” IE is present, the UEproceeds toand continues the gNBB access procedure. In this example, present means that the gNBB has included the “barred” indication to prevent legacy UEs from attempting to access channels that the legacy UEs are not capable of using. However, the present indication indicates to new UEs that the “barred” indication was for this reason and that since new UEs have the capability of accessing the channels that are less than 5 MHz, the new UEs may proceed. In contrast, if the further value is not present, this would signal to the new UE that the “barred” indication was for some other reason and both the legacy UEs and the new UEs are barred from accessing this cell. That operation where the new UE is also barred from accessing the cell is described below.

110 512 512 110 120 512 110 120 If the further value is not present, the UEproceeds to. In, the UEomits the attempt to access the gNBB. As described above, the operationrepresents a scenario in which the UEsupports a new channel design of the gNBB but is still not allowed to access the cell.

6 FIG. 600 600 110 110 120 120 shows a second method diagramaccording to various exemplary embodiments. The method diagrammay be understood to be applicable to scenarios wherein a UE (e.g., the UE) is attempting to access a cell utilizing a new channel design (e.g., sub-5 MHz). It should be understood that the UEmay be camped on a first cell (e.g., gNBA) and is considering whether to switch to a new target cell (e.g., gNBB).

602 110 120 604 110 600 In, the UEreceives a physical layer cell identity (PCI) from the gNBB. In, the UEdetermines whether the PCI is within a first range or a second range of values. The first range of values may be understood to be the existing PCI values [0-1007], and the second range of values may be understood to be the proposed expanded range of PCI values [1008-2015], though any ordinal relationship for the values is arbitrary (either range can be “first” or “second”). The method diagramis described with respect to the legacy PCI range of [0-1007] being the “first” range.

110 110 606 120 If the UEdetermines that the received PCI is in the first range, the UEproceeds toand continues target cell access procedures with the gNBB.

110 110 120 110 606 120 If the UEdetermines that the received PCI is in the second range and if the UEis a new UE capable of supporting the channel design of the gNBB, the UEwill continue toand continues target cell access procedures with the gNBB.

110 110 110 608 120 If the UEdetermines that the received PCI is in the second range, and the UEis a legacy UE, the UEwill continue toand omit an attempt to access the gNBB, e.g., the legacy UE will not attempt to access the cell because the UE does not support channels of less than 5 MHz.

In a first example, a processor of a user equipment (UE) is configured to receive, from a target cell, a cell identification (ID) number and determine the cell ID number is in one of a first range of values or a second range of values, wherein the first range of values indicates a channel being served by the target cell is a first type of channel and the second range of values indicates the channel being served by the target cell is a second type of channel.

In a second example, the processor of the first example, further configured to determine the UE only supports the first type of channel, when the cell ID number is in the second range of values, omit an attempt to access the target cell.

In a third example, the processor of the first example, further configured to determine the UE supports the first type and the second type of channel and attempt to access the target cell.

In a fourth example, a user equipment (UE) comprising a transceiver to communicate with a network and the processor of any of the first through third examples communicatively coupled to the transceiver.

In a fifth example, a processor of a base station is configured to broadcast a cell identification (ID) number, wherein the cell ID number is in one of a first range of values or a second range of values, wherein the first range of values indicates a channel being served by the base station is a first type of channel and the second range of values indicates the channel being served by the base station is a second type of channel and when a user equipment (UE) supports the first type and the second type of channel, permit an access attempt by the UE.

In a sixth example, the processor of the fifth example, wherein the cell ID number is generated using

where

In a seventh example, the processor of the fifth example, wherein the cell ID number is generated using

where and

In an eighth example, the processor of the fifth example, wherein the first type of channel is greater than or equal to 5 MHz.

In a ninth example, the processor of the fifth example, wherein the second type of channel is less than 5 MHz.

In a tenth example, a base station comprising a transceiver to communicate with a user equipment (UE) and the processor of any of the fifth through ninth examples communicatively coupled to the transceiver.

In an eleventh example, a processor of a user equipment (UE) configured to receive a master information block (MIB) from a target cell, decode the MIB, determine, based on information in the MIB, a channel served by the target cell is barred and determine, based on further information in the MIB, that the UE is not barred from using the channel.

In a twelfth example, the processor of the eleventh example, wherein the information comprises a value of a cellBarred information element (IE) of the MIB.

In a thirteenth example, the processor of the eleventh example, wherein the further information comprises a value of an information element (IE) in the MIB that is not a cellBarred IE.

In a fourteenth example, the processor of the eleventh example, wherein the channel comprises a bandwidth less than 5 MHz.

In a fifteenth example, a user equipment (UE) comprising a transceiver to communicate with a network and the processor of any of the eleventh through fourteenth examples communicatively coupled to the transceiver.

In a sixteenth example, a processor of a base station configured to encode a master information block (MIB) for a channel served by the base station, the MIB comprising a value of a first information element (IE) indicating a first type of user equipment (UE) is barred from accessing the channel, the MIB further comprising a value of a second IE indicating a second type of UE can access the channel and broadcast the MIB.

In a seventeenth example, the processor of the sixteenth example, wherein the first type of UE does not support channels having a bandwidth less than 5 MHz.

In an eighteenth example, the processor of the sixteenth example, wherein the second type of UE supports channels having a bandwidth less than 5 MHz.

In a nineteenth example, the processor of the sixteenth example, wherein the channel has a bandwidth less than 5 MHz.

In a twentieth example, the processor of the sixteenth example, wherein the first IE comprises a cellBarred IE.

In a twenty first example, the processor of the sixteenth example, wherein the second IE comprises a single bit value.

In a twenty second example, a base station comprising a transceiver to communicate with a user equipment (UE) and the processor of any of the sixteenth through twenty first examples communicatively coupled to the transceiver.

Those skilled in the art will understand that the above-described exemplary embodiments may be implemented in any suitable software or hardware configuration or combination thereof. An exemplary hardware platform for implementing the exemplary embodiments may include, for example, an Intel x86 based platform with compatible operating system, a Windows OS, a Mac platform and MAC OS, a mobile device having an operating system such as iOS, Android, etc. The exemplary embodiments of the above described method may be embodied as a program containing lines of code stored on a non-transitory computer readable storage medium that, when compiled, may be executed on a processor or microprocessor.

Although this application described various embodiments each having different features in various combinations, those skilled in the art will understand that any of the features of one embodiment may be combined with the features of the other embodiments in any manner not specifically disclaimed or which is not functionally or logically inconsistent with the operation of the device or the stated functions of the disclosed embodiments.

It is well understood that the use of personally identifiable information should follow privacy policies and practices that are generally recognized as meeting or exceeding industry or governmental requirements for maintaining the privacy of users. In particular, personally identifiable information data should be managed and handled so as to minimize risks of unintentional or unauthorized access or use, and the nature of authorized use should be clearly indicated to users.

It will be apparent to those skilled in the art that various modifications may be made in the present disclosure, without departing from the spirit or the scope of the disclosure. Thus, it is intended that the present disclosure cover modifications and variations of this disclosure provided they come within the scope of the appended claims and their equivalent.